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Cholesterol and Heart Disease
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early 2,200 Americans die of cardiovascular disease daily, with an average of one death occurring
every 40 seconds. An estimated 7.1 million Americans
have experienced a heart attack during their lifetimes.
Those who survive a heart attack often go on to have
another. More than 7 percent of Americans have some
type of cardiovascular disease, and one out of every
six deaths in the United States is due to coronary
heart disease alone.1 Eating habits and other lifestyle
factors play a large role in determining the risk of
heart disease and may prevent or even reverse this
condition.
Atherosclerosis
in Asia, Africa, and Latin America typically have total cholesterol
levels of about 125-140 mg/dl.4
Atherosclerosis is a common form of heart disease, in which
plaques of cholesterol and other substances (similar to small tumors) form in the artery walls and eventually restrict blood flow.
This constricted circulation leads to less oxygen for the heart muscle, resulting in chest pain (angina), usually following exercise or
excitement. It also stresses the heart muscle to the point of failure,
which is what happens during a heart attack.
Cholesterol
What Is Cholesterol?
Cholesterol is not the same as fat. If you had a bit of cholesterol
on the end of your finger, it would look like wax. The liver manufactures cholesterol and sends it out to other parts of the body for
the production of hormones and cell membranes. Based on the
results of the Framingham Heart Study and other research, the
ideal cholesterol level is below 150 mg/dl. At that point, coronary
artery disease is very unlikely. Unfortunately, nearly 107 million
Americans have cholesterol levels more than 200 mg/dl,1 dangerously close to 225 mg/dl, which is the average cholesterol level of
coronary artery disease victims.5
According to the 2010 USDA Dietary Guidelines, the federal
government’s recommended maximum for dietary cholesterol
intake is still as high as 300 mg. Both the American Heart Association and the National Cholesterol Education Program recommend
less than 200 mg per day for people at risk for cardiovascular disease.6 The amount of cholesterol in one egg exceeds this recommended maximum amount.
What Is Atherosclerosis?
Atherosclerosis is not caused by old age. Examination of American casualties during the Korean and Vietnam wars showed
significant atherosclerosis by age 18 or 20.2 Their Asian counterparts, raised on diets consisting mainly of rice and vegetables,
had much healthier arteries. The elderly are more likely to have
heart conditions not because of genetics, but because they may
have indulged in unhealthful habits, like smoking and poor diet,
for longer periods of time. Your doctor can tell you if you are one
of only about 5 percent of the population with a genetic tendency
toward heart disease. Many studies show the connection between
lifestyle choices and heart health. An article published by Caldwell
Esselstyn Jr., M.D., in the American Journal of Cardiology explains
that stenting and bypass surgeries may only be a solution for a
minority of patients, while a transition to a plant-based diet free
of cholesterol proves to be a more effective treatment.3
In 1948, William Castelli, M.D., began to monitor the population of Framingham, Mass., to study what factors influenced the
rate of heart disease.4 Castelli’s study showed that a cholesterol
level exists, below where coronary artery disease does not occur.
Framingham data show that only patients with cholesterol levels
of less than 150 milligrams per deciliter (mg/dl) achieve the lowest
coronary artery disease risk. In the first 50 years of the Framingham Heart Study, only five subjects with cholesterol levels of less
than 150 mg/dl developed coronary artery disease. Rural residents
Different Types of Cholesterol
When cholesterol is transported in the bloodstream, it is packed
into low-density lipoproteins (LDL), sometimes called the “bad
cholesterol.” Although LDL is necessary in limited quantities
(LDL delivers cholesterol to various parts of the body), a high LDL
cholesterol level can dramatically increase your risk of a heart
attack. The Centers for Disease Control and Prevention analyzed
data from 2005-2008 that examined prevalence, control, and treatment of high LDL levels. Around 71 million American adults (33.5
percent) had high LDL levels, while only 34 million (48.1 percent)
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and most other animal products contain substantial amounts of
saturated fat. This is another good reason to avoid these foods. A
few vegetable oils are also high in saturated fats. These are known
as tropical oils: palm oil, palm kernel oil, and coconut oil. Many
packaged foods contain hydrogenated oils. These are both high in
saturated fat and chemically hardened to make them solid at room
temperature to increase their shelf life. While liquid vegetable oils
are much better than animal fats and tropical oils, all fats and oils
are natural mixtures of saturated and unsaturated fats. Therefore,
none of them will do your coronary arteries any good, and consumption should be kept to a minimum.
The following chart shows the percentages of saturated fat in
different kinds of fat:
received treatment. Twenty-three million (33.2 percent) had their
LDL controlled.7 When cholesterol is released from dead cells it
is picked up for disposal by high-density lipoproteins (HDL), the
“good cholesterol.” When doctors measure cholesterol levels, they
first look at total cholesterol as a quick way to assess a person’s risk.
For a more exact guide, they divide the total level by the HDL level.
Heart attack risk is minimized by having a lower total cholesterol
and a higher proportion of HDL cholesterol. The ratio of total
cholesterol to HDL should be less than 4 to 1. Unfortunately, the
average American male’s ratio is much higher than that, at 5 to 1.
Vegetarians, on the other hand, average only about 2.8 to 1.3.
Smoking and obesity lower HDL; however, vigorous exercise
and foods rich in vitamin C may increase it.8
How to Lower Your Cholesterol
Decrease Cholesterol Intake
Since our bodies make plenty of cholesterol for our needs, we
do not need to add any in our diet. Cholesterol is found in all foods
that come from animals: red meat, poultry, fish, chicken, eggs,
milk, cheese, yogurt, and other dairy products. Choosing lean cuts
of meat is not enough; the cholesterol is mainly in the lean portion.
Many people are surprised to learn that chicken contains as much
cholesterol as beef, 25 mg per ounce.9 Every 4-ounce serving of beef
or chicken contains 100 mg of cholesterol. Most shellfish are also
very high in cholesterol. All animal products should be avoided for
this reason. No foods from plants contain cholesterol, since plants
do not have a liver to produce it. Every 100 mg of cholesterol in
your daily diet adds roughly five points to your cholesterol level,
although this varies from person to person. In practical terms, 100
mg of cholesterol is contained in 4 ounces of beef or chicken, half
an egg, or three cups of milk. People can reduce their cholesterol
levels dramatically by changing the foods they eat. For every 1
percent you reduce your cholesterol level, you reduce your risk of
heart disease by 2 percent.10 For example, a reduction from 300 mg/
dl to 200 mg/dl (i.e., a one-third reduction) will yield a two-thirds
reduction in the risk of a heart attack. For some people, the benefits
are even greater.
Animal Fats
Tropical Oils
Vegetable Oils
Beef Tallow 50%
Coconut Oil 87%
Canola Oil 12%
Chicken Fat 30%
Palm Oil 49%
Corn Oil 13%
Pork Fat (lard) 39%
Palm Kernel Oil 82%
Cottonseed Oil 26%
Olive Oil 13%
Peanut Oil 17%
Safflower Oil 9%
Sesame Oil 14%
Soybean Oil 15%
Sunflower Oil 10%
While the saturated fat in oil increases your cholesterol level,
the unsaturated fats cause other health problems, including increased free-radical production, an impaired immune system, and
increased body weight.
Go Vegan
A diet based on plant foods—grains, beans, vegetables, and
fruits—is the best way to keep saturated fat intake low and to avoid
cholesterol completely. A vegan diet is free of all animal products
and yields the lowest risk of heart disease.
Two large cohort studies and one meta-analysis found that vegetarians had a much lower risk of dying from heart disease than
nonvegetarians.11 A study from 2007 in the Journal of Nutrition
found that a single fatty meal can cause the heart to beat harder
and raise blood pressure. A high-fat, fast-food meal usually has
42 grams of fat, while a typical healthful meal would have around
1.3 grams of fat.12 One study showed that people who adopt a
vegetarian diet reduce their saturated fat intake by 26 percent
and significantly lower cholesterol levels in just six weeks. A more
recent study revealed that when participants switched to a strict
low-fat vegetarian diet for about two weeks, they lowered their total
serum cholesterol and blood pressure by 11 percent and 6 percent
respectively, and men lost an average of 5.5 pounds and women an
average of 2.2 pounds.13
In addition to the very low levels of fat in a typical vegetarian
diet, vegetable protein helps decrease the risk for heart disease.
Researchers in a 2014 study put 198 patients with cardiovascular
disease on a diet without fish, meat, dairy, or added oils. Eightynine percent of the participants adhered to the diet, and of that
group, 81 percent improved their symptoms and experienced fewer
complications from heart disease. In addition, they lost an average
of 18 pounds,14 while 22 percent saw a complete reversal of their
Decrease Fat Intake, Especially Saturated Fats
Keeping total fat intake low is an important way to lower
cholesterol and reduce the risk of other chronic diseases. Animal
products, including meat and dairy products, as well as fried food
and vegetable oils are all loaded with fat. The food industry reports
the fat content by weight, which allows the water content to throw
off the measurements and make these products look more healthful
than they actually are. The most important piece of information to
look for is the percentage of calories from fat. In the leanest cuts
of beef, about 30 percent of the calories come from fat. Skinless
chicken is nearly as high at 23 percent. Even without the skin,
chicken is never truly a low-fat food. Most cheeses contain 60 to 80
percent of calories from fat, and ice creams often contain 45 to 65
percent. Butter, margarine, and oils of all types typically contain
95 to 100 percent of calories from fat. Grains, beans, vegetables,
and fruits have less than 10 percent of their calories coming from
fat. Animal products also contain saturated fat, which causes the
liver to produce more cholesterol. Unsaturated fats do not have this
effect. Saturated fats are easy to spot because they are solid at room
temperature, whereas unsaturated fats are liquid. Beef, chicken,
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been clear, vegetarian diets are lower in fat and sodium and may
have other blood pressure-lowering effects.
Some of these factors include the potassium, magnesium, antioxidants, and fiber found in plant-based foods. The National Heart,
Lung and Blood and Institute performed a study in which people
consumed a low-fat diet rich in fruits and vegetables. The results
showed a drop in blood pressure, possibly due to the increased
dietary levels of potassium and magnesium.21 Additional studies
report that consuming 5-10 servings per day of fruits and vegetables also reduces blood pressure.22
An additional benefit is reduced iron storage in vegetarians.
Studies have shown strong links between iron and heart disease
and hypertension.23
condition.15 Studies show that replacing animal protein with soy
protein reduces blood cholesterol levels even when the total amount
of fat and saturated fat in the diet remains the same.16
Fiber: The Added Advantage of a Vegetarian Diet
Soluble fiber slows the absorption of some food components,
such as cholesterol, and reduces the amount of cholesterol the liver
produces. Every 10 grams of fiber per day reduces the risk of dying
by 10 percent.17 Oats, barley, beans, and some fruits and vegetables
are all good sources of soluble fiber. There is no fiber in any animal
product.18 An average American eats 10 to 15 grams of fiber per day.
The recommended daily amount is 20-35 grams per day. Eating a
vegetarian diet would allow you to consume more fiber from foods
including cereals, dried beans and peas, fruits, vegetables, and
whole grains.
Other Factors
Other factors can have as great an effect on the heart as diet. A
healthful meal is not enough if it is followed by a cigarette. People
who smoke have a much higher risk of heart disease when compared to nonsmokers. Moderation is not good enough—it is essential to quit. A study done in 2013 showed that cigarette smokers
also tend to have more risky eating behaviors, such as eating less
fruits and vegetables, while consuming more fried or processed
foods.24 Physical activity is also important. Regular light exercise,
such as a daily half-hour walk, can cut death rates dramatically.
The American Heart Association recommends at least 30 minutes
of moderate-intensity aerobic activity at least five days per week
for a total of 150 minutes. If you enjoy more vigorous exercise,
the recommendation is only 75 minutes per week, averaging 25
minutes for at least three days a week.
Here are some popular activities and the number of calories they
burn per hour for a 150-pound adult:
Maintain Your Ideal Weight
Carrying excess weight can increase the risk for heart disease.
People who are thick around the middle (“apple-shaped”) are at a
higher risk than those who carry excess weight around the hips and
buttocks (“pear-shaped”).19 “Apple-shaped” people can lose weight
through a low-fat diet and aerobic exercise. Visceral fat surrounds
the organs and can release dangerous chemicals, some of which increase the risk of heart disease. Subcutaneous fat is found under the
skin and is not as hazardous. In 2008, a study in the journal Obesity
determined that if obesity rates continue unchanged through 2030,
86.3 percent of adults will be overweight or obese, the prevalence
of childhood obesity will double, and one out of every six health
care dollars will go toward overweight and obesity-related costs.20
Activity
Calories Burned
Per Hour
Bicycling
400
Canoeing
180
Cooking
180
Dancing, Ballroom
240
Gardening
480
Golf
345
Jumping Rope
570
Finally, stress takes a toll on the heart. Daily life is full of events
that cause our hearts to beat a bit faster and drive up our blood
pressure.25 Reducing stress means keeping your challenges within
a range you can manage. Adequate rest and techniques for stress
reduction, meditation, or yoga can be very helpful. That being said,
taking control of the other factors cannot undo the effects of a bad
diet. A study done in 2006 showed that overweight women who exercise are at a greater risk for heart disease than women who do not
exercise at all but are at a normal weight. The overweight women had
an 87 percent increased risk for higher LDL cholesterol as opposed
to the 14 percent increased risk for normal BMI in active women.26
The only way to maintain a healthy heart is an all-encompassing
healthful lifestyle that incorporates a varied, low-fat, vegetarian
diet, daily physical activity, and stress reduction. The American
Public Health Association conference in 2009 found that omni-
Blood Pressure
High blood pressure is also a risk factor for heart disease and
can lead to strokes and other serious health problems. Fortunately,
this is another area where we can benefit by controlling our eating
habits. Salt has an effect on blood pressure and should be kept to a
minimum. The Dietary Guidelines state that daily sodium intake
should be less than 2,300 mg; people over age 51 (about half of the
U.S. population) should reduce their intake even more to 1,500 mg.
On average, Americans consume around 3,400 mg/day. Numerous
studies have shown that vegetarians have lower blood pressure
than nonvegetarians. A low-fat, high-fiber vegetarian diet, even
without reduced salt intake, can lower blood pressure by as much
as 10 percent. While the biological explanation for this has never
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vores who cut out meat from their diets experienced great improvements in their moods.27
• Prevent and Reverse Heart Disease by Caldwell Esselstyn Jr., M.D.
• The McDougall Plan by John McDougall, M.D.
And Now the Good News: Reversing Heart Disease
References:
1. Go AS, Mozaffarian D, Roger VL, et al, and the American Heart Association Statistics
Committee and Stroke Statistics Subcommittee. Heart disease and stroke statistics—2014
update: a report from the American Heart Association. Circulation. 2014;129:e28-e292.
2. Esselstyn CB Jr. Resolving the coronary artery disease epidemic through plant-based
nutrition. Prev Cardiol. 2007;4:171-177.
3. Esselstyn CB Jr. Updating a 12-year experience with arrest and reversal therapy for
coronary heart disease (an overdue requiem for palliative cardiology). Am J Cardiol.
1999;84:339-341.
4. Castelli WP. Making practical sense of clinical trial data in decreasing cardiovascular risk.
Am J Cardiol. 2001;88:16F-20F.
5. Castelli WP. The new pathophysiology of coronary artery disease. Am J Cardiol.
1998;82:60T-65T.
6. Spence JD, Jenkins DJA, Davignon J. Dietary cholesterol and egg yolks: not for patients
at risk of vascular disease. Can J Cardiol. 2010;26:e336-e339.
7. Centers for Disease Control and Prevention (CDC). Prevalence, treatment, and control of
high levels of low-density lipoprotein cholesterol—United States, 1999-2002 and 20052008. MMWR Morb Mortal Wkly Rep. 2011;60:109-114.
8. Trout DL. Vitamin C and cardiovascular risk factors. Am J Clin Nutr. 1991;53:322S-325S.
9. Pennington JAT. Bowes and Church’s food values of portions commonly used. New York:
Harper and Row; 1989.
10. The Lipid Research Clinics Coronary Primary Prevention Trial results. II. The relationship of reduction in incidence of coronary heart disease to cholesterol lowering. JAMA.
1984;251:365-374.
11. Craig WJ, Mangels AR; American Dietetic Association. Position of the American Dietetic
Association: vegetarian diets. J Am Diet Assoc. 2009;109:1266-1282.
12. Jakulj F, Zernicke K, Bacon SL, et al. A high-fat meal increases cardiovascular reactivity
to psychological stress in healthy young adults. J Nutr. 2007;137:935-939.
13. McDougall J, Litzau K, Haver E, Saunders V, Spiller GA. Rapid reduction of serum cholesterol and blood pressure by a twelve-day, very low fat, strictly vegetarian diet. J Am Coll
Nutr. 1995;14:491-496.
14. Masarei JR, Rouse IL, Lynch WJ, Robertson K, Vandongen R, Beilin LJ. Vegetarian diet,
lipids and cardiovascular risk. Aust NZ J Med. 1984;14:400-404.
15. Esselstyn CB Jr., Gendy G, Doyle J, Golubic M, Roizen MF. A way to reverse CAD? J Fam
Pract. 2014;63:356-364b.
16. Carroll KK, Giovannetti PM, Huff MW, Moase O, Roberts DC, Wolfe BM. Hypocholesterolemic effect of substituting soybean protein for animal protein in the diet of healthy young
women. Am J Clin Nutr. 1978;31:1312-1321.
17. Chuang SC, Norat T, Murphy N, et al. Fiber intake and total and cause-specific mortality
in the European Prospective Investigation into Cancer and Nutrition cohort. Am J Clin Nutr.
2012;96:164-174.
18. Swain JF, Rouse IL, Curley CB, Sacks FM. Comparison of the effects of oat bran and low-fiber wheat on serum lipoprotein levels and blood pressure. N Engl J Med. 1990;322:147-152.
19. Krotkiewski M, Bjorntorp P, Sjostrom L, Smith U. Impact of obesity on metabolism
in men and women: importance of regional adipose tissue distribution. J Clin Invest.
1983;72:1150-1162.
20. Wang Y, Beydoun M, Liang L, Caballero B, Kumanyika S. Will all Americans become
overweight or obese? estimating the progression and cost of the US obesity epidemic.
Obesity. 2008;16:2323-2330.
21. Sacks FM, Appel LJ, Moore TJ, et al. A dietary approach to prevent hypertension: a review
of the Dietary Approaches to Stop Hypertension (DASH) Study. Clin Cardiol. 1999;27:III6-III10.
22. Hypertension: major recommendations. Academy of Nutrition and Dietetics Evidence
Analysis Library Web site. http://www.andeal.org/tmp/pq71.pdf. Published August 14, 2014.
Accessed September 10, 2014.
23. Salonen JT, Salonen R, Nyyssonen K, Korpela H. Iron sufficiency is associated with hypertension and excess risk of myocardial infarction: the Kuopio Ischaemic Heart Disease
Risk Factor Study (KIHD). Circulation. 1992;85:759-764.
24. Mlčochová V. Smoking and Nutrition. Journal of Nutritional Therapeutics. 2013;2:213-217.
25. Schnall PL, Pieper C, Schwartz JE, et al. The relationship between job strain, workplace
diastolic blood pressure, and left ventricular mass index. JAMA. 1990;263:1929-1935.
26. Mora S, Lee I, Buring JE, Ridker PM. Association of physical activity and body mass index
with novel and traditional cardiovascular biomarkers in women. JAMA. 2006;295:1412-1419.
27. Beezhold BL, Johnston CS, Daigle DR. Restriction of flesh foods in omnivores improves
mood: a pilot randomized controlled trial. Poster presented at: American Public Health
Association's 137th Annual Meeting and Exposition; November 9, 2009: Philadelphia, PA.
28. Ornish D, Brown SE, Scherwitz LW, et al. Can lifestyle changes reverse coronary heart
disease? Lancet. 1990;336:129-133.
On July 21, 1990, The Lancet published the findings of Dean
Ornish, M.D., who demonstrated that heart disease can actually
be reversed without medications.28 Until then, most doctors did
not attempt to reverse heart disease, despite its ubiquity. Most believed that plaques of cholesterol and other substances that clogged
arteries would not go away. The traditional method of removal
was to wait until they became severe enough to warrant a bypass
or angioplasty. At the University of California in San Francisco,
Dr. Ornish tested the theory that a more potent diet, along with
other lifestyle changes, might actually reverse this condition. He
selected patients who had plaques that were clearly visible on angiograms and divided the patients into two groups. Half received the
standard care prescribed for heart patients. The other half began a
vegetarian diet with less than 10 percent of calories from fat. They
also began a program of modest exercise, avoided smoking, and
managed stress through a variety of simple techniques.
Dr. Ornish’s patients improved immediately, and they continued
to improve over the course of the year. While most of the patients
previously experienced the crushing chest pain of heart disease, “most
of them became essentially pain-free,” Dr. Ornish said, “even though
they were doing more activities, going back to work, and doing things
that they hadn’t been able to do, in some cases, for years.” Not only
did their cholesterol levels drop dramatically, but, after a year, 82
percent of the patients who followed Dr. Ornish’s program showed
measurable reversal of their coronary artery blockages. The plaques
dissolved without medications or surgery and had no side effects.
The control group, following the more traditional medical
routine, did not do as well. For most patients, chest pain did not
go away, but continued to get worse, and their plaques continued
to grow, cutting off blood flow to the heart more each day. Many
doctors still recommend “chicken and fish” diets, even though a
number of studies show that, in general, heart patients who make
such moderate dietary changes tend worsen over time. Those who
adopt a low-fat, vegetarian diet, get daily physical activity, avoid
tobacco, and manage stress, stand the best chance of reversing
heart disease. We now have the most powerful tools yet for gaining
control over the health of our hearts.
Suggested Reading
For more information on lowering cholesterol and other benefits of
a low-fat vegetarian diet, the Physicians Committee recommends:
• Power Foods for the Brain by Neal Barnard, M.D.
• Eat Right, Live Longer by Neal Barnard, M.D.
• Food for Life by Neal Barnard, M.D.
• Dr. Dean Ornish’s Program for Reversing Heart Disease by Dean
Ornish, M.D.
PhysiciansCommittee
for Responsible Medicine
PhysiciansCommittee.org
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